IT202100012644A1 - SYSTEM AND METHOD FOR CONTROLLING AN ELECTRONIC LOCK USING A RADIO SIGNAL - Google Patents

Description

SYSTEM AND METHOD FOR CHECKING A LOCK

ELECTRONICS THROUGH A RADIO SIGNAL

DESCRIPTION

TECHNICAL FIELD

The present invention refers to the sector of access control systems using wireless devices. In particular, the invention refers to a system for opening the lock of a car by means of a user terminal equipped with a wireless communication system, for example a smartphone.

STATE OF ART

Vehicle rental services, what? such as those for renting rooms or apartments, require a person to give the user an electronic key to use the vehicle or access the room or apartment.

To speed up operations and avoid the presence of personnel on site for the delivery of the electronic key, various systems have been devised that allow the door of a car or an apartment to be opened using a smartphone.

Korean patent application KR20130041865A provides for installing a barcode reader in the car door. The user is provided with a smartphone application on which he receives the barcode once the machine has been rented. Is the door opened by placing the barcode near the? of the reader.

Korean patent application KR20190021777A discloses a car sharing system in which the user can open a car using a smartphone. The user activates the Bluetooth of the smartphone and authenticates with the on-board diagnostic system (OBD) of the machine. The OBD system identifier is sent from the smartphone to a remote system which returns the data to the smartphone which is sent to the OBD system via Bluetooth. Once the latter has authenticated the data, he opens the car door.

Both solutions described in KR20130041865A and KR20190021777A, however, do not apply to most of the series machines currently on the market.

Some car sharing and car rental systems hide one of the car keys inside the car. When the user enters a car identification code (manually or by reading a bar code) in the car sharing app, does the app send a Bluetooth command to a relay? who presses the hidden key allowing the opening of the car. The user will find then a second key in the machine that can? use it to turn on the machine. This solution ? For? unsafe, as in the event of theft of the car both keys are lost and the insurance company may not be liable for the theft.

In general, modern systems for access control with radio frequency devices provide security mechanisms that are increasingly? complex to make cloning a remote control difficult. For example, car RKE (Remote Keyless Entry) systems are equipped with rolling code technology that allows for the generation of dynamic, non-repeatable codes. Although this allows a good level of security, on the other hand it makes the integration of the RKE system with other platforms difficult or expensive, especially the IoT (Internet of Things) ones.

? therefore felt the need for a system that allows the user to control access to a vehicle or room/apartment in a simple and fast way.

OBJECTS AND SUMMARY OF THE INVENTION

? object of the present invention is to overcome the drawbacks of the prior art.

In particular, ? object of the present invention to allow access control with wireless devices which is both safe and simple.

These and other objects of the present invention are achieved by means of a method, a system and a device, incorporating the characteristics of the attached claims, which form an integral part of the present description.

According to a first aspect, the invention? directed to a method of controlling an electronic lock by a radio signal. A user device sends a user command to open or close the electronic lock to a command device located near the lock. of the electronic lock. The control device generates a baseband digital signal from sampling data of an original signal which is included in the user command, and transmits a command radio signal by modulating the baseband digital signal with a modulation type and one or more transmit frequencies contained in the user command.

This solution therefore allows the electronic lock to be controlled in a simple way by means of a user device. For example, a user can receive on your phone the parameters that characterize a command signal sent by a remote control of the lock. Through the telephone the user can? what? generate a command containing these parameters and allow the command device to generate a radio signal that reproduces that of the remote control, and thus command? the electronic lock.

In one embodiment, the sampling data comprises a sampling frequency and samples of the original signal obtained by sampling the original signal at the sampling frequency. The control device transmits the samples of the original signal with a repetition frequency equal to the sampling frequency.

In another embodiment, the sampling data comprises a sampling frequency, an initial logical value of the original sampled signal, one or more time duration data, each time duration data representing a time interval in which the baseband digital signal maintains its logic value constant. Does the control device transmit the initial logic value for a time equal to a first datum of time duration of said one or more? time duration data. If in the command signal c?? also a second time duration datum, then, after a period of time equal to the first time duration datum, the control device transmits a signal with a logic value different from the initial logic value for a period of time equal to the second time duration datum . This solution allows you to reduce the amount? of data that must be transmitted to the command device so that? can generate a command radio signal that reproduces the original radio signal.

In one embodiment, the one or more transmission frequencies present in the command signal, are acquired by the command device through a key acquisition procedure destined to acquire one or more? broadcast frequencies. The key acquisition procedure includes the steps of

- receive the original signal,

- measure an indicator of the strength of the received radio signal, ed

- identify said one or more? transmission frequencies such as the frequency or frequencies of the original signal received which corresponds to a signal power value higher than a predetermined threshold.

Advantageously, then the key acquisition procedure further comprises the step of determining the type of modulation as a function of the number of transmission frequencies identified.

There? it therefore allows the control device to be used not only to control the electronic lock, but also to record the signals of the remote control and acquire the information necessary to reproduce the radio signal of the remote control.

In one embodiment, a programming device transmits, in encrypted form, the transmission frequency, the modulation type and the sampling data to the user device. Alternatively, the user device retrieves this data from a remote database.

These solutions make it possible to keep the parameters that characterize the radio control signals of the electronic lock outside the control device.

Advantageously, then, the control device communicates with the user device by means of a wireless communication protocol, preferably Bluetooth, different from that used by the control device to send commands to the electronic lock.

According to a second aspect, the invention? directed to a control device of an electronic lock comprising a wireless communication module for receiving from a user device a user command to open or close the electronic lock. The command device then comprises means for commanding the electronic lock and a unit? control device operatively connected to a wireless communication module and to the means for commanding the electronic lock so as to command the opening or closing of the electronic lock in response to the receipt of the user command. The means for controlling the electronic lock comprise a radio signal transmitter. The unit control ? configured to generate a digital baseband signal from sampling data of an original signal which is included in the user command, and to supply the transmitter with the digital baseband signal. The unit control ? also configured to set the transmitter in such a way as to transmit a radio command signal obtained by modulating the baseband digital signal with a type of modulation and one or more? transmit frequencies contained in the user command.

Advantageously, the control device comprises a radio signal receiver operatively connected to the unit? control. The unit control ? configured for:

- receiving through said radio signal receiver the original radio signal sent by a remote control configured to control the electronic lock (31,81),

- measure an indicator of the strength of the received radio signal, ed

- identify the? one or more? transmission frequencies as the frequency or frequencies of the original signal received which corresponds to a signal power value above a predetermined threshold,

- determine the type of modulation according to the number of transmission frequencies identified,

- send the? one or more? transmitting frequencies and the type of modulation to a programming device for storage in a database.

According to a further aspect, the invention is directed to an access control system comprising an electronic lock suitable for blocking or allowing access to a compartment, a user device suitable for sending an opening or closing command of the electronic lock, and a command device suitable for communicating with the user device and with the electronic lock. The command device? of the type indicated above and better described below.

Further characteristics and purposes of the present invention will become clearer from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will come described hereinafter with reference to some examples, provided for explanatory and non-limiting purposes, and illustrated in the accompanying drawings. These drawings illustrate different aspects and embodiments of the present invention and, where appropriate, reference numerals illustrating similar structures, components, materials and/or elements in different figures are indicated by like reference numerals.

Figure 1 schematically shows a system for controlling an electronic lock of a car by means of a radio command sent from a user device.

Figure 2 shows a control device for use in the system of Figure 1.

Figure 3 illustrates a block diagram of the electronic circuit of the device of Figure 2.

Figure 4 ? a flowchart of a procedure for detecting the electronic key in figure 1.

Figure 5 ? a flowchart of a procedure for registering an opening command of the machine in figure 1.

Figure 6 ? a flow chart of a signal sampling procedure of figure 7 implemented during the recording procedure of figure 5.

Figure 7 shows the sampling of a baseband digital signal obtained from the demodulation of a radio signal generated by the key in figure 1.

Figure 8 schematically illustrates the database of the system of figure 1.

Figure 9 ? a flowchart of a procedure performed by a user device to command the opening or closing of the electronic lock in figure 1.

Figure 10 ? a flowchart of a procedure performed by a command device to generate an electronic lock opening radio signal, which replicates the radio signal of the key in figure 1.

Figure 11 shows a baseband digital signal generated by the control device of figure 1 for generating the radio signal for opening and closing the electronic lock.

Figure 12 schematically shows a system for controlling an electronic lock of a door by means of a radio command sent from a user device.

DETAILED DESCRIPTION OF THE INVENTION

While the invention? susceptible to various modifications and alternative constructions, some embodiments provided for purposes of explanation are described below in detail.

It must be understood, however, that there is no no intention of limiting the invention to the specific embodiment illustrated, but, on the contrary, the invention is intended to cover all modifications, alternative constructions, and equivalents which fall within the scope of the invention as defined in the claims.

In the following description, therefore, the use of ?for example?, ?etc.?, ?or? indicates non-exclusive alternatives without limitation, unless otherwise indicated; the use of ?also? means ?including, but not limited to? unless otherwise indicated; the use of ?includes / includes? means ?includes / includes, but not limited to? unless otherwise indicated.

With reference to Figure 1, a system 100 is described for opening a machine 30 by wireless command sent from a smartphone 20 or other user device. This system can find application in a car rental or car-sharing service.

The system 100 comprises a control device 1 capable of recording radio signals sent by a remote control, in this case the remote control ? the key that controls the opening and closing of a car.

As shown in figure 2, the control device 1 comprises a case 10 inside which ? an electronic circuit 11 schematized in figure 3 is arranged. The case 10 is preferably rigid to protect the electronic circuit and fixing means 12 can be associated or integrated with it to fix it on a wall. For example, the fastening means can comprise a hook and loop fastening system of the Velcro? type; in this case, a part of the system, for example the layer with the hooks is glued to the case, while the other layer, with the slots, is fixed, for example glued, to the glass or other surface of the machine.

The electronic circuit 11 includes a wireless communication module 13 for communicating with an external device. In the example described here, the wireless communication system 13 ? a Bluetooth communication system through which the control device 1 can? communicate with a user device 20, for example a smartphone or tablet, and with the electronic lock 31 of the car 30.

The electronic circuit 11 then comprises a radio receiver 14 and a radio transmitter 15 respectively capable of receiving and transmitting radio signals, in particular in the UHF band and above. especially between 280 MHz and 960 MHz.

A unit of control 16, for example a microcontroller, ? operatively connected to the wireless communication module 13, to the receiver 14, to the transmitter 15 and to a group of LEDs 17 of different colours, which, in the example considered here, are three and have red, blue and green colours.

The control device 1 also comprises, inside the case 10, a power supply module 18, preferably a battery, capable of supplying electric energy to the entire electric circuit 11. In one embodiment, in addition to or as an alternative to one battery, the power module can? include a connector for connection to a source of electrical power, for example pu? comprise a connector which is inserted into a cigarette lighter of the car to transform a 12V voltage into the supply voltage of the electronic circuit 11 or for recharging the battery if present.

The unit control 16 ? configured to bring the control device 1 into different operating states to which different functions of the device itself correspond.

If there is no Bluetooth connection, the unit? control 16 ? configured to put the device into standby. In this state the LEDs 17 are off and energy consumption is reduced to a minimum.

When the wireless communication module 13 establishes a Bluetooth connection with a nearby device, the unit? control 16 brings the device 1 to the IDLE state. In this state the unit? control panel 16 flashes the blue LED and waits to receive a command from the nearby device.

In the example of figure 1, the system 100 comprises two types of devices which can be located in the vicinity of the control device 1. A first type? the programming device 50 that ? equipped with a programming application 51 for programming the control device 1. This device 50 can? be a server computer, a tablet, a smartphone or a cloud network of computers. In figure 1 ? represented a server computer only for clarity and distinction from the other type of devices, the user devices 20, which are instead equipped with a user application 21.

Operatively, in a first step the programming application 51 proceeds with the programming of the control device 1 first proceeding to detect the presence of a radio signal 41 sent by a remote control 40, which in this example is? the car key 30, and then proceeding to record the opening and closing commands.

After authenticating itself to device 1 and having established the Bluetooth connection, the programming application 51 then sends device 1 a key detection command called DET_KEY.

When the unit? of control 16 receives the command of detection key DET_KEY, the unit? control brings the device to the DETECTION state. The unit control then turns off the blue LED and performs a key detection method that ? described here with reference to the flowchart of figure 4.

After the start of the key detection procedure (step 400), the unit? control 16 activates the UHF receiver 14 (step 401). The receiver 14 listens for radio signals (41) sent by the key 40 and measures the power of the received signals, in particular it measures the received signal strength indicator (RSSI, Received Signal Strength Indicator).

The unit control 16 turns on the red LED (step 402) to signal the user to press the button of the key within a predetermined time interval t0, for example 5 seconds.

The receiver 14 therefore remains listening (step 403) and if it does not detect any radio signal in the predetermined time interval t0, then the unit? controller 16 sends (step 404) an error message to programming application 51 via wireless communication module 13 and interrupts the key detecting procedure (step 405).

If, on the other hand, the user presses the key to open the key and the receiver 16 identifies a transmission frequency of the radio signal sent by the key 40 (frequency which corresponds to an RSSI value higher than a predetermined threshold, for example 140) , then the? unit? of control 16 (step 406) turns on the green LED and controls the receiver 14 (step 407) starting a tuning phase to identify the type of modulation.

In the example considered here, the system ? set to distinguish between two possible modulations (ASK, Amplitude Shift Key, or FSK, Frequency Shift Key), then in the tuning phase the receiver measures the RSSI of the received signal in a band of frequencies arranged around the transmission frequency detected, for example +/- 150kHz from the detected frequency, to check if it finds another frequency which corresponds to an RSSI value higher than a predetermined threshold, for example 140. Preferably, during the tuning step the receiver scans the band of interest around the previously identified frequency, at much smaller frequency intervals (eg 10 times smaller) than those used in the first listening step (step 403). If the receiver detects a single RSSI peak, then the unit? control determines that it is ASK modulation, while if the receiver detects two peaks, then the unit? control determines that it is FSK modulation.

The unit control keeps the green LED on until it has completed the characterization operations of the command signal 41 (i.e. identification of the transmission frequencies and the type of modulation) sent by the key, or a predetermined time interval t1 passes, for example 5 seconds. In order to allow detection, while the LED ? green the user can? press more times the opening button of the key.

If not, then the unit? control returns to step 404: sends an error signal and interrupts the procedure.

If so, the unit? control 16 turns off the green LED (step 408) and creates (step 409) a data packet (called KEYS) containing information relating to the transmission frequency/s identified and the type of modulation. For example, in the case described here, where the command signal can? be modulated with ASK and FSK modulation, the KEYS data packet can? comprising a transmission frequency f0 and a frequency shift ?f. Where at the end of the tuning procedure a single transmission frequency had been detected, the KEYS packet would include the value of the frequency detected and a value of 0 (zero) for the frequency shift ?f. Where at the end of the tuning procedure two transmission frequencies were detected, the KEYS packet would include the value of one of the two frequencies and a value of ?f equal to the difference between the two frequencies. In this embodiment, the value of ?f therefore indicates the type of modulation. ? however, it is possible to envisage other embodiments in which the information on the type of modulation is explicitly transmitted, for example by setting the value 1 or 0 to a determined bit of the KEYS packet.

Finally, the unit? control 16 transmits (step 410) the KEYS packet to the programming application 51 through the wireless communication module 13, and interrupts the procedure (step 411).

The data packet KEYS is then stored by the programming application 51 in a data bank 52 accessible by the application itself. The database 52 contains, for each key, an identifier (which can be entered by the user via the user interface of the programming application or be generated by the application itself), a KEYS packet with the data characterizing the key command signal (transmission frequencies and modulation type), and data representing key opening and closing commands. Overall, therefore, for each key, sampling data is stored in the database 52 which, when sent to the control module, makes it possible to reproduce a control signal 41 (for opening or closing) sent by the key and consequently actuate the electronic lock 31.

To acquire the data representing the key opening and closing commands, the programming application 51 sends the control device 1 a SEND_PACK command followed by a KEYS packet to start a key command recording procedure illustrated below with reference to the registration of a machine opening command. The same procedure is followed to record the closing command of the machine.

As illustrated in the flowchart of figure 5, upon receipt of the SEND_PACK command and the KEYS package, the unit? control enters a state called ?CAPTURE?, and starts the key command recording procedure (step 500). The unit control 16, therefore, enables the UHF receiver to receive the frequencies defined in the KEYS packet (step 501) and turns on the red LED (step 502) to signal to the user that he can? press the key button within a predetermined time t2, for example 5 seconds.

The receiver 14 therefore remains listening (step 503) and if it does not detect any radio signal in the predetermined time interval t2, then the unit? controller 16 sends (step 504) an error message to programming application 51 via wireless communication module 13 and interrupts the key detecting procedure (step 505).

If the receiver 14 detects the radio signal of the command sent by the key, then the unit? control 16 starts the recording (step 506) of the radio signal as illustrated in figure 6, where the recording procedure 506 of a radio signal S(f) received by the receiver 14 is exploded.

After detecting the command radio signal, the UHF receiver starts demodulating it and outputs the corresponding digital signal S(t), illustrated in Figure 7, which varies over time. The unit then proceeds to initialize the DATA packet by inserting inside:

? the fc sampling frequency used during recording, for example a frequency between 125Khz and 1Mhz (step 5061);

? the logic value of the digital signal S(t) output from the UHF receiver (step 5062). In the example in figure 7, at time T0 the logic value ? low, i.e. it has a value of 0;

Subsequently, the unit? control starts a counter i (step 5063) by increasing it with a frequency equal to the sampling frequency, ie by increasing it every time interval ?t equal to 1/fc.

At each clock cycle of the counter, ie each ?t (step 5064), the unit? of control verifies the logical value of the digital signal S(t) (step 5065) and, if this is not ? changed, then proceeds to increment counter i (step 5068).

Otherwise, if the logical value of the signal S(t) ? changed, then (step 5067) the unit? control saves in the DATA packet a datum DT equal to the value of the counter i, corresponding to the number of clock cycles in which the signal S(t) remains at the same logic value. Alternatively, ? Is it possible to record in the DATA packet the time interval passed since the last variation of the state of the signal S(t) sampled, i.e. the datum DT recorded ? equal to DT=i? ?t. With reference to the example of figure 7, the first variation of state of the signal S(t) occurs at T1, therefore in this embodiment DT ? equal to T1. In both cases, DT ? a time datum, which represents a time (measured in clock cycles, i, or in seconds) elapsed between two digital signal state changes or between the start of signal recording (T0) and a subsequent state change.

After recording the DT time data, the unit? check (step 5068) checks whether the conditions for terminating signal recording are met, i.e. checks whether ? finished a maximum recording time (for example 2 seconds), or if yes? reached the maximum size of the data packet DATA to be transmitted (for example, 2048 bytes). If not, then the counter i is reset to zero (step 5063) and the recording is continued by repeating the steps indicated above, otherwise the recording ends.

How will you see? in the following, this sampling process allows to replicate the signal without knowing in advance the characteristics of the radio signal of the control 40, such as speed? transmission rate (bits per second) and type of encoding (e.g. NRZ, Manchester, or other). Also, like this ? Is it possible to reduce the complexity? of the system and the risk of registration errors (because it is not necessary to interpret the data). The system is then very reliable where the signal is replicated, given that the reproduced signal has temporal dynamic characteristics very similar to the original signal.

At the end of the registration, the unit? control 16 switches off the red LED (step 507) and creates (step 508) a DATA packet containing data which allow the sampled signal S(t) to be reconstructed. In the example described here, these data include the initial logic value S(0) of the demodulated digital signal S(t) and the data (i or ?T) which represent the time interval between two changes of logic value of the signal S(t ). Alternatively, in the recording phase all the values of the samples S(ti) could be recorded in the DATA packet, even if there? would need a DATA pi package? long.

Finally, the unit? control sends (step 509) the DATA packet to the programming application 51 through the wireless communication module 13 and terminates the procedure (step 505).

At this point, the? programming application 51 can? updating the database 52 by loading the data of the signal recorded for the key 40.

Figure 8 illustrates an example of a database 52, which includes:

? a key identification field (520) which corresponds to the license plate of the machine, e.g. ER888ST;

? a signal parameter field (521) which contains a KEYS packet 601 with data characterizing the radio signal generated by the key, ie transmission frequencies and modulation type;

? an opening command field (522) which contains one or more? packets DATA 602 each containing the data of the sampling of an opening signal cos? as recorded in the procedure of figure 6, i.e. the sampling frequency fc, the initial value S(0) recorded in step 5062 and the time data (e.g. DT1 and DT2) recorded in step 5067.

? a closing command field (522) which contains one or more? packets DATA 603 each containing the data of the sampling of a closing signal cos? as recorded in the procedure of figure 6.

Clearly other solutions are possible, in which the key identifier ? different from the license plate of the machine and in which the database includes an identifier of the thing to which ? associated with the key: the car in this example, a room or an apartment in another case.

In the example of figure 8, for each key the database 52 therefore comprises command data 600 which allow the device 1 to replicate a radio signal equal to the radio signal 41 generated by the key 40. The command data include the parameters 601 which characterize the radio signal to be replicated (transmission frequencies and type of modulation), and the sampling data of the opening 603 or closing 604 command signals of the electronic lock 31.

When a user needs to open or close the electronic lock 31, he starts the user application 21 on his smartphone 20 which sends an opening or closing command of the lock 31 of the machine 30 by executing a key command replication procedure described below with reference to figure 9.

Upon starting the key command replication procedure (step 900), the user application 20 connects to the command device 1 (step 901) via Bluetooth connection, and sends to the device 1 (step 902) a user command 210 via which the opening or closing of the lock 31 of the machine 30 is commanded. The user command 210 comprises, in particular, a SEND_PACK command followed by a KEYS packet and a DATA packet containing the sampling of the opening signal or close you want to send. The procedure ends (step 903) with the sending of the command.

The unit control unit 16 of device 1 receives the user command 210 and starts (1001) a command generation procedure illustrated below with reference to figure 10.

First of all, the unit? of control sets the radio transmitter 15 (step 1002) to generate radio signals according to the signal parameters contained in the KEYS packet, for example to generate a signal with FSK modulation and with transmission frequencies equal to 433.98 MHz and 434.02 MHz for the two logical values 0 and 1 of the signal.

Subsequently, the unit? control unit 16 processes the data of the DATA packet to generate a baseband digital signal starting from sampling data contained in the data packet. The baseband digital signal SG(t) generated by the unit? control 16 ? shown in figure 11.

In detail, the unit? control unit 16 processes the DATA packet and extracts the first logic value of the sampled signal (S(0)) and sets the transmitter to transmit this value (step 1003). In the example considered here, the transmitter is set to transmit a signal v=S(0) having logic value 0.

Set the transmitter, the unit? control sets a control variable k to 1 (step 1004), and takes the kth DT value recorded in the DATA packet (step 1005). In this phase k=1, therefore the first value of DT is taken, indicated with DT1. In the example considered here, DT represents the number i of clock cycles for which the transmission must continue before a change of state of the signal, but the same procedure can? be applied to the case where DT represents time ?T.

At this point the unit? of control starts a counter n (step 1006) which is increased with a frequency equal to the sampling frequency contained in the DATA packet received with the user command 210. At each clock cycle (ie for each value of n), the unit? check (step 1007) if DTk clock cycles have passed, that is if ? after a time ?Tk, i.e. if the radio transmitter 15 has transmitted the signal v for a time equal to ?Tk..

If so, then the unit? of control (step 1008) sets the transmitter to invert the logic value transmitted by the transmitter, increases the value of k of a?unit? (step 1009), and returns to step 1005: takes the next time duration datum, restarts counter n. If not, on the other hand, it checks whether the data to be transmitted have run out (step 1010). If the data to be transmitted have run out (step 1012), then the procedure terminates. Otherwise (step 1011) counter n is incremented (step 1011) and one starts again to check if ? a time equal to DTk has elapsed (step 1007).

To clarify, let us suppose that the user command 210 contains the data packet relating to the recording of the signal S(t) of figure 7. In this case, the signal S(t) has a low initial logic value, i.e. S(0)=0 , and remains in this logical state for a DT1 time equal to 4 clock cycles, therefore the unit? control 16 imposter? the transmitter to start transmitting the low logic value (0) and rester? in this condition for four clock cycles, i.e. until n=4. At that point the unit? control sets the transmitter to transmit the inverse value with respect to that transmitted up to then, ie sets the transmitter to transmit the high logic value, 1. At this point the unit? control takes the second time data DT2 present in the DATA packet and will continue? to impose the transmission of the high logic value for a time DT2 equal to T2-T1. The process is then repeated until the complete transmission of all data, i.e. until there are more? time intervals ?T to be taken from the DATA packet.

In one embodiment, the user application 21 receives the DATA and KEYS packets from the programming application 51 or other remote application that accesses the database 52. For example, when the user rents the car, the service center sends the user application 20 the license plate or other identification of the machine 30, and the data for opening the machine 30.

In another embodiment, the user application 21 autonomously retrieves the data to be sent to the control device 1 for opening or closing the machine 30. For example, the user enters the user application 21 an identification code of the machine which is sent to the remote application which accesses the database 52 and returns the requested data to the user application 21. Still, in other embodiments the user application 21 directly accesses the database 52 and retrieves the data.

The data of the opening or closing commands are preferably extracted from the database 52 according to a FIFO rule (first in first out) so as to allow the system to function also with locks which use the rolling code system. In the case of codes that can be used only once, once the data have been extracted, they are canceled from the database 52, otherwise they can be left and reused later, even if there is it is not preferred and could lead to security risks.

From the description above ? it is evident how the system described above allows to achieve the proposed aims by allowing the user to open or close the machine by means of a command from a smartphone at the same time guaranteeing a secure access system and without the need to modify the machine.

The user who wants to rent a car, therefore, no longer has to? queue up and wait for authorized personnel to hand over the car keys. The user can open the machine using the user application as described above. Inside the car you will find? a key with which to use the car and then, at the end of the rental, can it? leave the key in the machine and close the latter using the user application.

? therefore evident, to a technician of the branch, that ? It is possible to make modifications and variations to the solution described with reference to the figures without thereby departing from the scope of protection of the present invention as defined by the attached claims.

For example, the user device 20 and the control device 1 can communicate using any wireless communication protocol other than Bluetooth, for example Zigbee?, NFC (Near Field Communication) or others. Clearly the user device 20 and the control device 1 must be equipped with the relative communication module.

All communications between the various devices in the system can be encrypted for security reasons. For example, the fact that the user's device transmits the sampling data and the parameters characterizing the original signal (frequencies and modulation) in encrypted form to the remote server, allows the information to be kept confidential to the subject who manages the server, who could be different from the provider of the service.

Again, it is possible to provide a command device without the UHF receiver 14. In this case the parameters of the radio signal to be transmitted (carrier frequency, modulation and opening or closing command data packet) are acquired in another way, for example they can be loaded into the database 52 directly from the remote control manufacturer.

? also evident that the? invention ? however applicable to other sectors where access to a closed room or compartment is controlled by an electronic lock. In this case, command device 1 will be placed inside the room or compartment in such a position as to be able to receive commands from the user application 21 and be able to generate wireless signals for opening or closing the electronic lock.

There? ? illustrated, for example, in figure 8, where the control device 1 is arranged on the wall of a room 80 closed by a door 81 provided with an electronic lock 81 which can be controlled by means of a remote control 4000 equipped with opening (4001) and closing (4002) buttons, when pressed, radio signals (4003) are sent to command the electronic lock 81.

Also in this case it is possible to implement the procedures described above for recording the commands of the remote control by means of the command device 1 and recording these commands in the database 52. The system 1000 of figure 8 therefore allows the user equipped with user application 21 to retrieve the data to open or close the door 80 from the database and to send the commands to the command device 1 exactly as illustrated above with reference to figure 7.

Claims (12)

1. Method of controlling an electronic lock (31,81) by a radio signal (300), wherein a user device (20) sends (902) a user command (210) for opening or closing the electronic lock (31,81) to a command device (1) arranged in the vicinity? of the electronic lock (31,81), and in which the control device (1) controls the electronic lock (31,81), characterized in that the control device (1) generates a baseband digital signal starting from sampling data (602,603) of an original signal (41) which are included in the user command (210), and transmits a radio command signal ( 300) by modulating the baseband digital signal with a type of modulation and one or more? transmit frequencies (601) contained in the user command (210). The method according to claim 1, wherein the sampling data comprises a sampling frequency and samples of the original signal obtained by sampling the original signal at said sampling frequency, and in which the control device transmits, with a repetition frequency equal to the sampling frequency, the samples of the original signal. The method according to claim 1, wherein the sampling data comprises a sampling frequency, an initial logic value (S(0)) of the original sampled signal, one or more time duration data (DT1, DT2,DT3,DT4), each time duration data representing a time interval in which the baseband digital signal maintains its logic value constant, and in which the control device (1) transmits the initial logic value (S(0)) for a time equal to a first datum of time duration (DT1) of said one or more? time duration data (DT1, DT2,DT3,DT4). 4. Method according to claim 3, in which, after a period of time equal to said first data of time duration (DT1), the control device (1) transmits a signal with a different logic value from the initial logic value for a period of time equal to a second datum of time duration (DT2) of said one or more? time duration data (DT1, DT2,DT3,DT4). 5. Method according to any one of the preceding claims, in said one or more? broadcast frequencies are acquired through a key acquisition procedure to acquire said one or more? transmission frequencies, said key acquisition procedure comprising the steps of - receive the original signal, - measure an indicator of the strength of the received radio signal, ed - identify said one or more? transmission frequencies such as the frequency or frequencies of the original signal received which corresponds to a signal power value higher than a predetermined threshold. 6. Method according to claim 5, the key acquisition procedure further comprises the step of determining the type of modulation as a function of the number of transmission frequencies identified. 7. Method according to any one of the preceding claims, wherein a programming device (50) transmits, in encrypted form, to the user device (20) the sampling data (602,603), the modulation type and one or more ? broadcast frequencies (601). 8. Method according to any one of claims 1 to 5, wherein the user device (20) retrieves from a remote database (52) the sampling data (602,603), the modulation type and one or more broadcast frequencies (601). 9. Method according to any one of the preceding claims, wherein the control device (1) communicates with the user device (20) by means of a wireless communication protocol, preferably Bluetooth, different from the one used by the control device (1) to send commands to the electronic lock. 10. Control device (1) of an electronic lock (31,81) comprising a wireless communication module (13) for receiving from a user device (20) a user command (210) for opening or closing the electronic lock (31,81), means for controlling the electronic lock (31.81) a?unit? control device (16) operatively connected to a wireless communication module (13) and to the means for commanding the electronic lock (31,81) so as to command the opening or closing of the electronic lock in response to the receipt of the user command (210) characterized in that the means for controlling the electronic lock (31,81) comprise a radio signal transmitter (15) and by the fact that the? unit? control (16) ? configured for generating a digital baseband signal from sampling data (602,603) of an original signal (41) which is included in the user command (210), to supply the transmitter with the baseband digital signal, to set the transmitter in such a way as to transmit a radio command signal (300) obtained by modulating the baseband digital signal with a type of modulation and one or more? transmit frequencies (601) contained in the user command (210). 11. Device according to claim 10, further comprising a radio signal receiver (14) operatively connected to the unit? control (16), and in which the unit? control (16) ? configured for - receiving through said radio signal receiver (14) the original radio signal (4003) sent by a remote control (40,4000) configured to control the electronic lock (31,81), - measure an indicator of the strength of the received radio signal, ed - identify the? one or more? transmission frequencies as the frequency or frequencies of the original signal received which corresponds to a signal power value above a predetermined threshold, - determine the type of modulation according to the number of transmission frequencies identified, - send the? one or more? transmission frequencies and the type of modulation to a programming device (50) for storage in a database (52). 12. Access control system, comprising an electronic lock (31.81) designed to block or allow access to a compartment (30.80), a user device (20) adapted to send an opening or closing command to the electronic lock (31,81), a control device (1) according to claim 10 or 11, able to communicate with the user device (20) and with the electronic lock (31,81).